Siege of Fort Vincennes

The Siege of Fort Vincennes was a Revolutionary War frontier battle fought in present-day Vincennes, Indiana won by a militia led by American commander George Rogers Clark over a British garrison led by Lieutenant Governor Henry Hamilton. Roughly half of Clark's militia were Canadien volunteers sympathetic to the American cause. After a daring wintertime march, the small American force was able to force the British to surrender the fort and in a larger frame the Illinois territory.

On January 29, 1779 Francis Vigo, an Italian fur trader, came to Kaskaskia to inform Clark about Hamilton's reoccupation of Vincennes. Clark decided that he needed to launch a surprise winter attack on Vincennes before Hamilton could recapture the Illinois country in the spring. He wrote to Governor Henry:

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